4 Chemistry for the Microbiologist, 91

Organization of Matter, 92

Chemical Elements, 92 Structure of Atoms, 92

Ions, 93

Atomic number and weight, 93

Isotopes, 93

Electron arrangements and chemical reactivity, 94 Molecules and Chemical Bonds, 94

Ionic bonds, 95

Covalent bonds, 95

Hydrogen bonds, 97

Isomers and the three-dimensional structures of molecules, 98

Functional groups, 98 Chemical Reactions, 99 Chemical Equations, 99 Equilibrium 99

Energy and Chemical Reactions, 100 Types of Chemical Reactions, 100

Enzymatic reactions, 100

Oxidation-reduction reactions, 102

CONTENTS xi

Acid-base reactions, 102

Condensation and hydrolysis reactions, 104 Molecules of Living Systems, 106 Water, 106 Carbohydrates, 107 Lipids, 108

Lipids are hydrophobic nonpolar molecules, 108 Proteins, 110

Protein structure, 112

Denaturation of proteins, 113 Nucleic Acids, 114

DNA, 114

RNA, 115

Other nucleotides, 115 Summary, 115

UNIT TWO

CELLULAR AND MOLECULAR MICROBIOLOGY

5 Cell Structure, 120

Cells, 121

Plasma Membrane: Movement of Materials into and out of Cells, 121

Structure of the Plasma Membrane, 122 Comparison of Archaebacterial and Eubacterial

Plasma Membranes, 123 Comparison of Eubacterial and Eukaryotic Plasma

Membranes, 124 Transport Across the Plasma Membrane, 124 Diffusion, 124 Osmosis, 125 Active Transport, 126 Group Translocation, 127 Cytosis, 127 Cell Surface, 128 Cell Wall, 128

Chemical composition of the bacterial cell

wall, 128 Comparison of Gram-positive and Gram-negative bacterial cell walls, 130 Bacterial Capsules and Glycocalyces, 133 Pili, 134

Bacterial Flagella, 135 Eukaryotic Flagella and Cilia, 137 Storage and Expression of Genetic Information, 140 Bacterial Chromosome, 140 Plasmids, 140

Nucleus of the Eukaryotic Cell, 141 Ribosomes, 142 Cellular Structure and Energy Transformations, 143 Sites of Chemiosmotic Generation of ATP in

Prokaryotic Cells, 144 Sites of Chemiosmotic Generation of ATP in Eukaryotic Cells, 145 Mitochondria, 145 Chloroplasts, 146 Segregation and Movement of Materials within Cells, 147

Cytomembrane System of Eukaryotic Cells, 147 Endoplasmic reticulum, 147 Golgi apparatus, 149 Lysosomes, 150 Vacuoles, 1150 Cytoskeleton, 150 Survival Through the Production of Spores and Cysts, 152 Bacterial Endospores, 152 Fungal Spores, 153 Protozoan Cysts, 153 Summary, 154

6 Cellular Metabolism, 157

Process of Metabolism within a Cell, 158

Role of Enzymes, 158

Coenzymes and Oxidation-reduction

Reactions, 159 ATP and Cellular Energy, 160 Metabolic Pathways and Carbon Flow, 161 Autotrophic and Heterotrophic Metabolism, 162

Autotrophic metabolism, 162

Heterotrophic metabolism, 163 Metabolic Pathways, 164 Respiration, 165

Glycolysis, 166

Krebs cycle, 168

Electron transport chain and chemiosmotic generation of ATP, 168

Aerobic respiration, 170

Anaerobic respiration, 171 Lipid and Protein Catabolism, 171 Fermentation, 173

Ethanolic fermentation, 174

Lactic acid fermentation, 174

Propionic acid fermentation, 176

Mixed-acid fermentation, 178

Butanediol fermentation, 179

Butanol fermentation, 179 Photosynthetic Metabolism, 179

Photoautotrophs, 180

Photoheterotrophs, 181

Photosystems and ATP generation, 181

Calvin cycle and C0₂ fixation, 183 Chemoautographic metabolism, 183

Sulfur oxidation, 183

Nitrification, 184 Nitrogen Fixation, 184 Methanogenesis, 185 Summary, 187